Bug fix: Single channel audio in plugin version wasn't working properly with 2 channel MPX output through sound card.

Bug fix: Fixed some uninitialized variables with Valgrind.

Bug fix: Fixed potential memory error when loading presets.

Bug fix: Incoming NANs could cause an exception in Absolute Highs.

Bug fix: Linux version: Solved hangup on start if no GUI could be opened (version 8.52).

Bug fix: strncpy calls protection added

Bug fix: SCA didn't work well (glitches) when more than 1 thread was used.

Bug fix: When the scheduler was used on a file with only partial preset data, the AGC was switched back to Old AGC mode.

Bugs: Added more NAN logging

Added Romanian translation and updated presets.

2017/11/15

v8.53

Bug fix: Multiband in RMS mode could be killed (compressors become inactive, limiting still worked) after feeding a NAN through it.

Bug fix: Auto EQ was missing from the Processing main page.

Bug fix: Increases NAN detection thresholds to avoid false positives.

SST: Web gui improvements.

SST: Web gui increased contrast.

SST: Improved installer.

SST: Updated and added presets.

2017/10/05

v8.52

WatchCat: Added Mac OS X version.

Stand alone version: Moved memory allocations to before actual audio is running to avoid hiccups after starting Stereo Tool.
Sound card buffer could be filled too much until you did a RESTART SOUND CARDS.

Made external RDS follower PLL much slower to avoid bad pilot.

Web interface: Added way to use it remotely without knowing the session ID (use ID -1).

Auto EQ: Updated default settings.

Omnia.9/9sg: AutoPilot smooth transition between pilot and no pilot.

Omnia.9/9sg: Made some build settings changes to avoid #define issues between projects.

Multiband compressors: Made a new mode where the slopes actually follow the settings.
Until now, they were compensated for the distance between bands. That might have been useful for some situations,
but made it harder to recreate the sound of other processors.

Multiband compressors: Improved Flat Tops in this new mode.

Multiband compressors: Fixed weird jumps in band behavior in this new mode.

Natural Dynamics: Changed the dB value calculation and range for "Reduce for jump above";
changed default setting to 6 dB (instead of 13). This reduces the effect of ND if the input signal is more dynamic.

GUI: Now displaying supported sample rates for each sound card.

Delossifier: Slightly improved the performance.

Delossifier: Fixed several strange bugs, that I've never seen cause any issues - but they might.

Stereo Image: Removed some code that wasn't used anymore but still doing calculatons on uninitialized values.

Bug fix: MPX Power calculation was wrong after switching to a different sample rate.

Bug fix: Fixed broken GUI display in AM mode when in full-screen

Added new and removed old presets.

2014/07/27

v7.50

Added new ACR (Attack Controlled Repeat) Stereo enhancer. Gives better control over amount of stereo, sounds more sparkling and can be set to boost transients more. You should probably turn Stereo Boost off when using this.

Added Watchdog, regularly checks that sound card inputs and outputs are working. If no audio runs for a longer period, sound cards and later Stereo Tool gets restarted (stand alone version only).

Added Exception handling: Exceptions should never occur, but if they do, they are now handled gracefully: They are logged and shown to the user, an attempt is made to continue processing, if that fails (exceptions keep occurring) Stereo Tool (stand alone version only) can be restarted automatically.

Bug fix: AGC could hang in some cases when enabling more bands. Fixed.

Bug fix: Phase rotation did not sound good at low latencies in version 6.10.

Bug fix: Time zone in RDS was wrong.

GUI improvement: Made waveform background black.

RDS: Adjusted behavior if no special characters (<, >, |, ||) are used: Word wrap with centering is selected by default. This was done for the Omnia 9 that uses the Stereo Tool RDS encoder; the behavior is now identical for both systems.

RDS: Ignoring trailing spaces for word wrap.

Added a lot of presets.

Added interface for blind users. Set environment variable STBLIND to 1 or YES.

Removed "Trumpet sound filter" from earlier versions that was intended to improve the quality of certain sounds, but also caused a lot of side effects (no longer needed due to the new phase rotation filter).

Removed Multiband HQ mode (no longer needed).

Made main window resizable and maximizable.

Bug: No 2 Stereo Tool instances can be loaded in a VST engine based using the same Stereo Tool DLL file. A popup now displays this message and gives a workaround.

Presets updated (now using Bass Boost and Phase Rotation where appropriate) or added.

RDS without stereo no longer generates a 19 kHz pilot tone.

In case of FM output, "normal output" is closer to the FM sound, and the FM sound is clipped better before 'FM Overdrive' - using FM Overdrive now leads to a 3% louder output signal than before with better quality.

Input and output volume meters blink in red to indicate clipping if the maximum volume is reached (input) or surpassed (output).

Loudness: Improved handling of female voices and xylophone-on-top-of-low-strings sounds, leading also to an overall more natural sound.

Re-organized Loudness window. Should be clearer now.

Stereo Boost: Added a filter that removes excessive reverb that occurs in some songs. The result is much closer to the original sound, but still with strongly increased stereo.

2009/10/20

v4.21

Bug fix: VST plugin version: Some version 4.00+ parameters were not saved.

Slightly improved some presets.

2009/10/18

v4.20

Loudness: Added a filter to reduce bass distortion. Bass levels can now be set much higher without getting more distortion than before, or kept at the same level for better sound quality.

Loudness: Added a deep bass boost filter that boost very low (up to about 70 Hz) bass sounds by about 1.5 dB (at 100 Hz the bass is about 0.8 dB softer though).

Loudness: Added a limiter to the Clean/Punch filter to remove distortion caused when setting it close to Punch. Moved Clean/Punch default setting closer to Punch.

Low Quality mode: Changed the processing that is used for low quality mode. Quality is much better than before, and the CPU load is reduced.

Low Latency mode: Fixed some issues in the low latency processing. Latency is now approx. 100 ms lower than before, quality is much closer to that of normal latency processing.

Noise gate: Noise reduction can now be set for each frequency band.

Added a number of presets with more bass.

Added Marino's Urban preset to Web Radio presets.

2009/09/10

v4.10

Added new stereo widening filter: Stereo Boost.

Updated most of the presets to use the new Stereo Boost filter.

Reduced the minimum value for the gap detection time.

2009/08/11

v4.05

Bug fix: No audio problem unless 'bypass' is used solved.

Bug fix: Too long delay in tray icon volume display solved.

Improved Hard Compression: Dance presets.

2009/07/19

v4.04

Bug fix: Under certain circumstances occasional hangups could occur. That should be solved now.

Single core systems were not properly recognized and used code that was optimized for multicore systems. The CPU load on single core systems should be slightly lower now.

2009/06/28

v4.03

Loudness filter: Improved the filter that detects high frequency distortion caused by very low frequencies. Low frequencies are now much louder, and distortion is greatly reduced.

Loudness filter: Added a slider to choose between clean sound (with ringing artifacts) or punchy, as-close-as-possible to the original sound. Punchy sounds a lot better, but it may introduce some distortion (which is largely solved by the fix on the previous line).

When opening a window that was already open, it jumps to the front now.

Stereo Tool logo added to the window title bar, also displayed now when using ALT-TAB.

Interface: When clicking on a panel which' window is already open, it jumps to the front.

2009/06/12

v4.00

Redesigned the interface. The main window is now smaller and less crowded. Each filter has its own window now, and many values are displayed in dB also.

The output displays in the main window are now synchronized to each other, and can be synchronized to the audio player sound card output.

Added a fix for the annoying "part of the previous song gets played at the start of the next song" problem in Winamp. Note that this fix is a workaround for what is essentially a problem of Winamp, and it may not be perfect.

Reorganized the Presets pulldown menu, and added the 10 last used preset files to the list. Also the currently selected preset is visible in the Presets pulldown button now.

Added more control over how the Loudness filter works. It's now possible to allow more highs or more lows to pass through (this may cause some distortion though).

Pre Limiter is now using perceptive volume instead of peak level for much better initial volume control.

Added a filter to remove remaining loud peaks after the Pre Limiter filter. The Pre Limiter works with a delay, the new filter is a lookahead filter that removes remaining peaks, which occur mostly at the start of a new track after some silence.

Final limiter now has an option to use less CPU power (in that case it doesn't preserve the volume).

Added a pre-final limiter filter for loud peaks (the normal Final Limiter is loudness preserving, but it doesn't handle very loud sounds well. This pre-final limiter filter removes those very loud sounds.)

Loudness filter: The Loudness filter can now handle much louder peaks than before. This even makes it possible to use the Loudness filter as a limiter.

Loudness filter: Loud "S" sounds now cause far less bass level reduction - so the sound is more stable.

Included the Singleband Compressor from versions 2.11 and below again. It's available from the Limiting & Loudness window.

Added some presets made by Vamprecords, SuperH and Bojcha.

Added a "Bypass all" button on the main window.

Added "FM RDS TA" button on the main window so traffic announcements can now be indicated without opening the FM configuration window.

Performance: On multicore systems, the processing now uses multiple threads. Some slower AMD dualcore PCs couldn't handle FM output in High quality, now they can.

Fixed a bug: The highpass filter seems to have been disabled when Multiband compression is turned on since version 3.50.

Fixed a bug that could cause blocks of bad pixels in the user interface.

Fixed a bug that caused presets to sound slightly different when they were selected while audio was playing.

Fixed a bug: On startup, even if Multiband HQ was ticked Multiband didn't run in HQ mode.

Greatly reduced the gaps that occur when switching between presets.

Uncoupled screen redraws from processing. This allows Windows to select a different CPU for screen updates on multicore systems, and they might get disabled temporarily on single CPU systems when the load is high.

2009/04/23

v3.55

Loudness filter: Louder and more stable bass sound.

Soundcard support (stand alone version, Direct Soundcard Output on plugin versions): No more stuttering when the output buffer is empty, instead a short break is inserted such that the buffer is filled again when playback resumes. (No change for ASIO output).

Stereo widener is now almost as strong as in versions before 3.51, but with far less artifacts than before. Especially low quality MP3s should sound a lot better.

FM transmitters: MPX filtering cleaned up further, noise level is now around 90 dB below the actual signal (used to be about 30 dB).

Very minor change in pre-filtering steps that should slightly improve the handling of loud high frequencies.

2009/04/02

v3.51

FM transmitters: Improved filtering for a cleaner MPX signal.

Stereo widener causes less artifacts, but also has a bit less effect.

2009/04/01

v3.50

Loudness filter: Recalibrated to achieve a much cleaner and louder sound. Distortion that was still present in version 3.40 is now nearly gone, and values up to 3.00 sound good.
Values up to 4.00 are now allowed.
Loud highs now have far less effect on the loudness of the other sounds - so it sounds much more stable.
Added a filter to improve trumpet sounds.
Improved quality and loudness of deep bass sounds.

Improved FM pre-emphasis to match the official specification (in older versions the pre-emphasis wasn't strong enough, so this new version sounds brighter.)

Volume slider now show both pre-emphasized and de-emphasized output levels.

Changed Multiband compressor to get a warmer output sound with lower peak levels.

Improved the HARD LIMIT filter to sound cleaner, cause far less pumping, and to achieve a louder output volume.

Hard Limit filter is now also used if Direct Sound Card Output is used.

Improved the composite limiter filter to cause far less pumping, and to achieve a louder and cleaner output volume.

Updated presets, added FM Extreme preset.

Improved Lowpass filter to filter closer to the selected lowpass frequency (important for AM presets).
Also the filtering quality is now much better - the spectrum above the filtering frequency is now really empty.

Bug fix: Fake stereo didn't work in version 3.40 - it does work again now.
The CPU load is about 5-10% higher than that of version 3.40 - measured using the FM Loud preset.

2008/12/03

v3.40

Loudness filter: Completely rewritten. Now reaches much louder sounds (up to +12 dB) with far less effects on the sound quality. Even notoriously difficult sounds such as xylophones are now handled without introducing distortion.

Added FM transmitter calibration. If you are having problems with your FM signal (caused by low quality transmitter equipment, sound card, long cables etc.), you can now configure Stereo Tool to accomodate for that. (On my system, stereo separation is increased by 15 dB after calibrating!)

Composite limiter now operates at 705.6 or 768 kHz. This removes peaks that were introduced by the lowpass filter of the sound card.

Hard limit now operates at 352.8 or 384 kHz. This removes peaks that were introduced by the lowpass filter of the sound card.

Removed the Loudness ++ option because it is no longer needed.

Tweaked the presets to take advantage of the improved Loudness filter (more punch).
The CPU load is roughly identical to that of version 3.30 in Low and Normal quality mode as long as the composite limiter oversampling is not used. And it will be a lot slower on PC's without SSE2 support.

Small (6-10%) performance improvement.
Improved Final limiter filter: More stable output.
Added Highpass filter to filter out low rumbling sounds (especially useful when playing from vinyl) and sounds that may interfere with FM stereo transmissions.
Added VST plugin version (beta!).

2008/08/16

v3.27

Huge performance improvement (48% faster than 3.26 - although still 6% slower than in versions 3.21 and older versions).
Improved Final limiter filter: More stable output.
Improved Loudness filter: Switch ("++") available to choose between loudest possible sound (same as in older versions) or slightly less loudness with much better sound quality.

2008/08/12

v3.26

Improved Loudness filter: Distortion caused when a large amount of high frequencies was present (mainly FM pre-emphasized sounds) is reduced.

Improved Loudness filter: Reduced pumping for loud bass or hi-hat sounds at high Loudness settings.
Spoken text for unregistered versions increased from once every 24 hours to once every 12 hours.
Pop-up added requesting to register (shown only once every 30 days).

2008/08/03

v3.23BETA

Redesigned Loudness filter processing: Same volume and clarity as older versions, but with quality of 3.22.
Far lower CPU usage for loudness filter in High Quality mode.
Redesigned Final Limiter and Loudness filter for better sound quality. Suggested new setting: 0.01 s.

Stand-alone version: Fixed a bug that caused crashes.
Stand-alone version: Fixed a bug that caused strange sounds on non-SSE2 machines.
Stand-alone version: Fixed a bug that could cause continuous hiccups in the sound when the CPU load was very high (unlikely).
Added more feedback on sound card problems: A red bar now indicates an error.
Improved the performance of the FM pre-emphasis filter.
Fixed a bug to support 32/64/128 kHz input for FM transmissions.
64/128 kHz input is now processed at 32 kHz if "Process as 44.1 kHz" is enabled (previously 64 kHz). This reduces the CPU load.

2008/06/05

v3.13

Improved sound quality for FM transmitters (brighter, better highs).
Save bug which caused Stereo Tool to keep starting up in simple mode fixed.
Fixed a bug which made it impossible to select Windows Audio Mapper as output device.
Fixed a bug that could cause Stereo Tool to produce silence when leaving Simple mode, restart was needed.

Re-added Channel Delay fake stereo filter (now part of the Stereo Image filter).
Fixed STS load file bug which could cause some values not to be refreshed.
Fixed STS load bug in Basic mode which could cause the sound to drop to silence.

Added Basic interface for easier control than the (original) Advanced interface.
Improved Compression (Loud) presets (better sound quality).
Solved a bug that could cause Winamp to crash when Stereo Tool was closed very quickly after opening it.

Bug fix: Startup problem in SAM4 solved. This bug may have caused other problems as well.

2008/04/05

v3.0

Greatly improved performance using hand-optimized SSE2 code.
Added dualband pre-limiter.
Increased number of multiband compressor channels from 8 to 10 for deeper bass sounds.
Added multiband clippers for a more stable sound with less remaining peaks.
Added multiband "feedback" loop which feeds the total output volume back into the multiband compressor, to enable better control of the maximum output volume.
Added multiband compressor HQ mode for much better bass quality.
Added multiband post filter for improved sound quality, when using agressive multiband compression settings.
Added possibility to limit the maximum phase difference between the two channels in the stereo image filter.
Added a 3-step final limiter to enable creating a completely flat output level without pumping or distortion.
Added a "loudness" filter which can make audio sound up to 5.5 dB louder without generating louder peaks.
Added FM stereo encoder for FM transmitters.
Added RDS encoder for FM transmitters (still very limiter in this version).
Added vertical scrollbar for small displays.
Added bypass mode: When iconified, right-click on the Stereo Tool icon to turn it on or off.
Updated the presets to make use of the new features.
Removed singleband compressor.
Removed "normal" interface, only simple and extended are left.

2007/??/??

v2.11

Bug fix: Clipping problem in 24 bit audio solved.

2007/03/18

v2.10

Added single bass speaker mode. This solves bass sound cancellation issues if a single bass speaker is used.
Added an automatic phasing (azimuth) detection and correction filter. This improves the sound of some recordings (including many cheap CDs with old music) and tapes.
Bug fix: "libguide" conflict with other plugins and SAM4 MP3 output resolved.